KR100982842B1 - Atomic layer deposition apparatus - Google Patents

Abstract

Disclosed is an atomic layer deposition apparatus capable of uniformly injecting a deposition gas and depositing a thin film evenly inside a deep trench on a substrate having a deep trench. The atomic layer deposition apparatus includes a shower head having a plurality of injection holes for injecting the deposition gas into the substrate and a plurality of intake holes for sucking the exhaust gas in the process chamber, wherein the injection holes and the intake holes are alternately arranged. do. Therefore, by alternately arranging the injection line and the intake line in the source area in the shower head, since the injection and exhaust of the gas is alternately performed quickly, the pumping effect occurs when the gas is injected into the deep trench. In addition, source gas is supplied deep into the trench to improve step coverage and film formation quality.

Shower Head, Injection Hole Pattern, Exhaust Hole Pattern, Step Coverage

Description

Atomic Layer Deposition Apparatus {ATOMIC LAYER DEPOSITION APPARATUS}

The present invention relates to an atomic layer deposition apparatus, and more particularly, to an atomic layer deposition apparatus capable of improving step coverage and film formation quality in a substrate having a deep trench.

In general, in order to deposit a thin film having a predetermined thickness on a substrate such as a semiconductor wafer or glass, physical vapor deposition (PVD) using physical collision such as sputtering and chemical vapor deposition using chemical reaction A thin film production method using (CVD; Chemical Vapor Deposition) is used.

Here, chemical vapor deposition includes atmospheric pressure chemical vapor deposition (APCVD), low pressure chemical vapor deposition (LPCVD), plasma organic chemical vapor deposition (Plasma Enhanced CVD), and the like. Plasma organic chemical vapor deposition has been widely used due to its advantages and fast film formation.

However, as the design rule of the semiconductor device sharply becomes fine, a thin film of a fine pattern is required, and the step of the region where the thin film is formed also becomes very large. As a result, the use of a monoatomic layer deposition (ALD) method capable of forming a very fine pattern of atomic layer thickness very uniformly and having excellent step coverage has been increasing.

The atomic layer deposition method (ALD) is similar to the conventional chemical vapor deposition (CVD) method in that it uses chemical reactions between gas molecules. However, conventional chemical vapor deposition methods inject a plurality of gas molecules into the process chamber at the same time to deposit reaction products generated above the substrate onto the substrate, whereas atomic layer deposition methods inject one gaseous material into the process chamber. It is different in that after injection it is purged to leave only the physically adsorbed gas on top of the heated substrate, and then inject other gaseous materials to deposit the chemical reaction product which occurs only on the upper surface of the substrate.

Thin films implemented through such an atomic layer deposition method have a very good step coverage (step coverage) characteristics, and has the advantage that it is possible to implement a pure thin film with a low impurity content has been widely spotlighted.

On the other hand, the conventional atomic layer deposition apparatus is a method of spraying different types of source gases while the shower head or susceptor rotates at a high speed, and a thin film is formed as the substrate sequentially passes through the source gas, so in the process chamber Source gases are mixed with each other, there is a problem that the film quality is reduced. Also, the deposition quality in the atomic layer deposition apparatus is affected by the uniform degree of the gas supply amount provided from the showerhead.

When the trench is formed in the substrate, it is difficult to sufficiently inject the source gas into the trench in the conventional atomic layer deposition apparatus. Here, simply increasing the injection pressure of the source gas injected from the shower head is not solved.

In particular, in the case of deep trenches, congestion may occur in the middle portion of the trench while the source gas is being injected, so that the source gas may not reach the inside of the trench, and when the second source gas is subsequently injected, the first source gas may be Since the reaction occurs only up to the injected depth, the thin film is not properly formed in the trench. In addition, even when the purge gas is stagnant in the trench, the source gas may not be properly injected to the inside of the trench, and thus, a thin film may not be properly formed in the trench and the film quality may be deteriorated. Therefore, it is necessary to develop a shower head capable of completely injecting the source gas to the inside of the trench, and without exhausting the source gas or the purge gas into the trench and completely exhausting the source gas.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and to provide an atomic layer deposition apparatus capable of increasing step coverage.

In addition, the present invention is to provide an atomic layer deposition apparatus that can improve the deposition quality.

According to embodiments of the present invention for achieving the above object of the present invention, the atomic layer deposition apparatus is formed with a plurality of injection holes for injecting the deposition gas to the substrate and a plurality of intake holes for sucking the exhaust gas, The injection hole and the intake hole have a shower head alternately arranged.

In an embodiment, the shower head is provided with a plurality of injection lines and intake lines defined by a plurality of injection holes and a plurality of intake holes disposed along a straight line, and the injection lines and the intake lines are parallel to each other at a predetermined interval. Is formed. In addition, the shower head is provided with a plurality of injection lines and a plurality of intake lines, the injection line and the intake line are alternately arranged. The pair of alternating injection lines and the intake line is defined as the injection intake group. For example, the jet intake group may be formed along a radial direction of the shower head. In addition, the plurality of jet intake groups may be disposed radially with respect to the center of the shower head.

In an exemplary embodiment, the shower head may include a source region in which source gas is injected and a purge region in which purge gas is injected into the substrate, and the injection intake group may be formed in the source region. Alternatively, the injection intake group may be formed in both the source region and the purge region.

On the other hand, according to another embodiment of the present invention for achieving the above object of the present invention, the atomic layer deposition apparatus is provided with a semi-batch type susceptor for supporting a plurality of substrates, a plurality of source regions and a plurality of purge The shower head includes a shower area including an area, and an exhaust line provided in the shower head to exhaust the exhaust gas in the process chamber and disposed at a boundary between the source area and the purge area. In the shower head, an injection hole for injecting deposition gas and an intake hole for sucking exhaust gas are formed in an injection area, and the injection hole and the intake hole are alternately disposed. Here, the exhaust line and the intake hole may be connected to different exhaust parts.

According to the present invention, first, by alternately disposing the injection hole and the intake hole in the shower head to prevent the stagnation of the source gas or purge gas in the trench to increase the injection efficiency of the source gas into the trench, the inside of the trench The quality of the formed thin film is improved and the step coverage is improved.

In addition, it is possible to improve the exhaust efficiency of the source gas or purge gas stagnant in the trench, and to improve the film formation quality.

Although the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, the present invention is not limited or restricted by the embodiments.

1 is a side cross-sectional view of an atomic layer deposition apparatus according to an embodiment of the present invention. FIG. 2 is a plan view illustrating an embodiment of the showerhead of FIG. 1, and FIG. 3 is a plan view illustrating a modified embodiment of the showerhead of FIG. 2. 4 is a perspective view illustrating a main portion of the showerhead of FIG. 2, and FIG. 5 is a perspective view illustrating a main portion of the showerhead according to a modified embodiment of FIG. 4. 6 is a cross-sectional view of the showerhead according to another modified embodiment of the showerhead of FIG. 4, and FIG. 7 is a side cross-sectional view of the showerhead of FIG. 6. 8 is a cross-sectional view of the showerhead according to another modified embodiment of the showerhead of FIG. 4.

9 is a side cross-sectional view illustrating main parts of the operation of the shower head according to the exemplary embodiments of the present invention.

Hereinafter, an atomic layer deposition apparatus according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 9.

Referring to FIG. 1, the atomic layer deposition apparatus 100 includes a process chamber 110, a showerhead 130, and a susceptor 120.

The process chamber 110 accommodates the substrate W to provide a space in which the thin film deposition process is performed.

Here, the substrate W may be a silicon wafer to be a semiconductor substrate. However, the present invention is not limited thereto, and the substrate W may be a transparent substrate such as glass used in a flat panel display device such as an LCD and a PDP. In addition, the substrate W is not limited in shape and size by drawing, and may have substantially various shapes and sizes, such as circular and rectangular plates.

A chamber exhaust 111 for exhausting exhaust gas is provided below the process chamber 110.

The susceptor 120 is provided in the process chamber 110 and supports the plurality of substrates (W). For example, the susceptor 120 is a semi-batch type having excellent throughput, and the plurality of substrates W are disposed to support one surface on the same plane, and the susceptor 120 is supported. ) Radially along the circumferential direction on the surface.

The susceptor 120 is rotatably provided so that the substrates W revolve around the center of the susceptor 120, and a rotation shaft 121 and the rotation shaft 121 are disposed below the susceptor 120. Is connected to the rotation drive unit 125 for rotating the susceptor 120 is provided.

The shower head 130 is provided above the process chamber 110 to provide deposition gas to the surface of the substrate W supported by the susceptor 120.

Deposition gas is collectively including a source gas containing a material constituting the thin film to be deposited on the surface of the substrate (W) and a purge gas for purging the source gas, in the present embodiment a plurality of different types of sources Gas is provided.

The shower head 130 is provided with an exhaust line 140 for exhausting unreacted deposition gas and residual deposition gas in the process chamber 110, and the exhaust line 140 and one side of the process chamber 110; The discharge unit 160 is provided to communicate with the exhaust gas exhausted from the exhaust line 140. One end of the discharge part 160 is connected to the exhaust line 140 through the process chamber 110, and the other end is connected to the exhaust part 165 provided outside the process chamber 110.

Hereinafter, the structure of the shower head 130 will be described in detail with reference to FIGS. 2 to 7.

As shown in FIG. 2, the shower head 130 includes a plurality of injection holes through which the deposition gas is injected, and the exhaust line 140 is provided.

The shower head 130 has an injection region 132 through which deposition gas is injected, and different gases are injected from the injection region 132. In detail, the injection region 132 includes a first source region 132a through which a plurality of different source gases are injected, a second source region 132b, and a plurality of purge regions 132c and 132d through which the purge gas is injected. Is done.

The exhaust line 140 penetrates through the shower head 130 to communicate with the inside of the process chamber 110, and a plurality of exhaust holes 141 are formed along the exhaust line 140.

Here, the exhaust holes 141 are formed at predetermined intervals along the longitudinal direction of the exhaust line 140. Here, the size, number and location of the exhaust holes 141 are not limited by the drawings, and holes of different sizes may be formed according to the displacement, or holes may be arranged at different pitch intervals. In addition, the exhaust hole 141 may have a structure such as a slit, not circular.

The exhaust line 140 is provided at a boundary portion of the injection zone 132, and serves to separate the injection zones 132. For example, four spraying regions 132 are formed in the shape of a fan in the shower head 130. In addition, the exhaust line 140 has a 'V' structure to maximize the area of the first and second source regions 132a and 132b, and is formed along a boundary line of the injection region 132. As shown in FIG. 2, the two 'V' shaped exhaust lines 140 are horizontally symmetrical and 'V' shaped vertices facing each other exist at the center of the shower head 130.

In the present exemplary embodiment, the exhaust line 140 has a 'V' shape, but the shape of the exhaust line 140 is not limited thereto. For example, the exhaust line 140 may have a variety of forms, such as a semi-circle or semi-elliptic shape.

A plurality of injection holes 131 through which the deposition gas is injected are formed in the first and second source regions 132a and 132b in the shower head 130, and a plurality of intake holes 135 through which the exhaust gas is sucked. Is formed.

Here, the plurality of injection holes 131 are disposed along a straight line on the shower head 130, and the plurality of intake holes 135 are also disposed in a straight line. Hereinafter, the injection holes 131 are disposed in a straight line shape. The injection line 131a is referred to, and the intake hole 135 is disposed in a straight line, the intake line 135a.

Meanwhile, as illustrated in FIG. 9, a trench T having a predetermined depth is formed in the substrate W. As shown in FIG. In the shower head 130 according to the present exemplary embodiment, the injection line 131a and the intake line 135a are alternately disposed to uniformly inject the deposition gas to the inside of the trench T.

As shown in FIG. 2, a plurality of injection lines 131a and a plurality of intake lines 135a are formed in the first and second source regions 132a and 132b, and the injection lines 131a and the intake air are formed. Lines 135a are alternately arranged with each other. In addition, a plurality of purge holes 131b for injecting purge gas are formed in the purge regions 132c and 132d.

The purge holes 131b are regularly arranged in the purge regions 132c and 132d. For example, the purge hole 131b may be disposed on a concentric circle centered on the center point of the shower head 130. Alternatively, the purge hole 131b may be disposed radially along the radial direction of the shower head 130.

The injection line 131a sprays the source gas in a straight line shape on the substrate W, and the source gas is uniformly sprayed on the entire surface of the substrate W as the substrate W rotates. In addition, the intake line 135a is formed in parallel with the mall injection line 131a at a position spaced apart from the spray line 131a by a predetermined interval.

For example, the injection line 131a is formed to inject the source gas into the substrate W in a straight line that is substantially orthogonal to the moving direction of the substrate W. FIG. As an example, the spray line 131a is formed to be parallel to the radial direction of the substrate W as the substrate W rotates. In addition, the length of the injection line 131a has a length that is equal to or longer than the diameter of the substrate (W).

Here, a pair of injection line 131a and an intake line 135a disposed in parallel to each other form a spray intake group 133, and a plurality of spray intake groups 133 are formed in the shower head 130.

The injection intake group 133 pumps the source gas injected into the trench T by alternately injecting and injecting the source gas to the surface of the substrate W so that the source gas is in the trench T. ) It is injected to the bottom of the inside.

In addition, as the gas is injected and exhausted alternately, there is an effect of improving the exhaust effect of the residual source gas and the purge gas in the trench (T).

On the other hand, one side of the intake line (135a) is provided with an exhaust (not shown) for providing a negative pressure to the intake hole 135 to suck the exhaust gas from the substrate (W). Here, the intake line 135a is not intended to exhaust the exhaust gas to the injection region 132, but provides a weak negative pressure to the substrate W to allow flow to the deposition gas inside the trench T. Since it is intended to form, the suction force is weak compared to the suction force formed in the exhaust line 140. Therefore, the intake line 135a and the exhaust line 140 are connected to different exhaust parts. Of course, the intake line 135a and the exhaust line 140 may be connected to the same exhaust unit.

On the other hand, in Figure 3 as a modified embodiment of the above-described shower head, the injection line 151a and the intake line 155a are formed not only in the source regions 152a and 152b but also in the purge regions 153a and 153d. Illustrated showerhead 150 to form group 153. The embodiment shown in FIG. 3 is substantially the same as the embodiment shown in FIG. 2 except for the intake group 153, the same reference numerals are used for the same components, and redundant descriptions will be omitted. do.

As shown in FIG. 3, each of the spraying regions 152 has three to five spray lines 151a and an intake line 155a. In addition, by alternately disposing the injection line 151a and the intake line 155a in the purge areas 153c and 153d, the purge gas may be sufficiently injected into the trench T as well as completely removed. As well as effectively purging the source gas in (T), by preventing the purge gas in the trench (T) it is possible to effectively prevent dilution of the source gas supplied subsequently.

In FIG. 3, reference numeral 151 denotes an injection hole of source gas, and reference numeral 155 denotes an intake hole.

The shower head 150 is formed such that the spray line 151a and the intake line 155a may be sprayed and intaked independently of the deposition gas and the exhaust gas in the shower head 150 without crossing each other.

Hereinafter, an internal structure of the showerhead 330 according to embodiments of the present invention will be described with reference to FIGS. 4 to 7. The showerheads shown in FIGS. 4 to 7 are substantially the same showerheads except for some structures of the showerheads, and components not shown in the drawings will be described with reference to FIG. 2.

Referring to FIG. 4, the shower head 330 is formed by combining two plates 330a and 330b to form a cavity 332 that becomes a supply passage through which the deposition gas S may flow.

A plurality of injection holes 331 penetrating the lower plate 330b are formed in the lower plate 330b disposed to face the substrate W so as to communicate with the inside of the cavity 332. The injection hole 331 injects the deposition gas S provided to the cavity 332 to the substrate W.

On the other hand, the injection holes 331 are arranged in a line to spray the deposition gas (S) to the substrate (W) in the form of a line approximately perpendicular to the moving direction of the substrate (W) 131a ; See FIG. 2).

A plurality of intake holes 335 are formed through the shower head 330 to suck the exhaust gas V from the substrate W. An intake passage 336 is provided on the upper plate 330a to provide a negative pressure to the intake hole 335 and become a flow path of the exhaust gas V sucked through the intake hole 335. For example, the intake hole 335 has a pipe shape connecting the substrate W and the suction passage 336 through the plates 330a and 330b. In addition, the suction passage 336 may have a straight pipe shape connecting upper portions of the plurality of intake holes 335.

The intake hole 335 is disposed along a straight line to form an intake line 135a (see FIG. 2). The intake line 135a is formed at a position spaced apart from the injection line 131a by a predetermined interval, and the intake line 135a and the injection line 131a are formed to be substantially parallel to each other.

FIG. 5 is a modified embodiment of the showerhead of FIG. 4, and unlike the showerhead illustrated in FIG. 4, the cavity in which the deposition gas S is provided in the showerhead 350 is doubled.

Referring to FIG. 5, three shower plates 350a, 350b, and 350c are stacked to form a first cavity 352a and a second cavity 352b therein. In addition, a plurality of first injection holes 351a are formed in the second plate 350b to provide the deposition gas S supplied to the first cavity 352a to the second cavity 352b. A plurality of second injection holes 351b for injecting the deposition gas S into the substrate W is formed in the third plate 350c.

The second injection hole 351b is disposed in a straight line to form the injection line 131a. Here, the shower head 350 may uniformly provide the deposition gas S to the spray line 131a and the spray region 132 by supplying the deposition gas S through the dual cavities 352a and 352b. There are advantages to it.

An intake hole 355 is formed through the shower head 350, and an intake passage 356 is formed on the first plate 350a to provide a negative pressure to the intake hole 355. The intake hole 355 may be formed in a pipe shape penetrating the plates 350a, 350b and 350c and the cavities 352a and 352b to suck the exhaust gas V independently of the deposition gas S.

6 and 7 illustrate another modified embodiment of the showerhead of FIG. 4.

6 and 7, a plurality of deposition gases penetrating the inside of the shower head 430 are not formed in which one cavity for providing the deposition gas S is formed in the space inside the shower head 430. The flow path 432 and the plurality of exhaust gas flow paths 436 are formed.

In detail, the deposition gas passage 432 and the exhaust gas passage 436 penetrate the inside of the shower head 430 in a horizontal direction to form a plurality of passages, and the deposition gas passage 432 and the exhaust passage. The gas flow passages 436 form independent flow passages without crossing or communicating with each other. Here, a plurality of injection holes 431 are formed through the deposition gas flow path 432 to provide the deposition gas S to the substrate W, and the exhaust gas V is formed on the substrate W. A plurality of suction holes 435 are formed through the exhaust gas flow path 436 to suck the gas.

For example, the deposition gas flow path 432 is formed in a straight line shape to form the injection line 131a, and a plurality of deposition gas flow paths 432 communicate with one side of the shower head 430, A deposition gas source 433. In addition, the exhaust gas flow path 436 is formed in a straight line parallel to the deposition gas flow path 432 at a position spaced apart from the deposition gas flow path 432 so as to form the suction line 135a. The plurality of exhaust gas flow passages 436 communicate with one side of the shower head 430 and are connected to the exhaust pump 437.

8 is a diagram for describing another modified embodiment of the showerhead of FIG. 4.

In the shower head 450 according to the exemplary embodiment illustrated in FIG. 8, a first cavity 452 for supplying the deposition gas S and a second cavity 453 in which the exhaust gas V flows are formed in dual forms. Has

In detail, the shower head 450 is formed by stacking the first to third plates 450a, 450b, and 450c, and each of the plates 450a, 450b, and 450c has the first cavity 452 therein. And the second cavity 453 are formed.

A plurality of injection holes 451 are formed to penetrate the third plate 450c to communicate the second cavity 453 and the inside of the process chamber 110, and the deposition gas is formed on the substrate W. Spray S).

An intake hole 455 is formed in the second plate 450b to communicate the first cavity 452 with the inside of the process chamber 110 and to suck exhaust gas V. Here, the intake hole 455 is formed through the second cavity 453, and is formed to form an independent flow path without communicating with the inside of the second cavity 453.

The injection hole 451 and the intake hole 455 are disposed on a straight line parallel to each other. For example, the injection hole 451 and the intake hole 455 may be disposed on a straight line that is substantially orthogonal to the moving direction of the substrate (W).

Here, in the above-described embodiments, the size, shape and pitch interval of the injection hole and the suction hole are not limited by the drawings, and may be changed by the source gas injection amount and the exhaust amount.

Referring to FIG. 9, the operation of the shower head 130 will be briefly described.

As shown in FIG. 9, when the substrate W having the trench T passes through the injection line 131a, the deposition gas S is injected from the injection line 131a to form the trench T. Source gas is injected into the inside. When the substrate W passes through the injection line 131a and passes through the intake line 135a, the deposition gas S injected into the trench T by the suction force generated in the intake line 135a. Flows out of the trench (T).

Here, the injection line 131a and the intake line 135a are spaced apart from each other by a predetermined distance, but are disposed at a relatively close position. In addition, the suction force formed in the intake line 135a does not suck all of the deposition gas S injected into the substrate W, but generates a flow in the deposition gas S inside the trench T. It is formed to an extent that can be made. That is, the intake line 135a generates a flow in the deposition gas S in the trench T, so that the deposition gas S may be sufficiently injected to the bottom surface of the trench T.

In addition, since the substrate W is continuously rotated and passes through the injection line 131a and the intake line 135a a plurality of times, injection and discharge of the deposition gas S are repeated in the trench T. This repetition of injection and discharge prevents stagnation of the deposition gas S in the trench T, so that the deposition gas S is smoothly injected and flows out.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

1 is a side cross-sectional view for explaining an atomic layer deposition apparatus according to an embodiment of the present invention;

2 is a plan view for explaining the showerhead of FIG.

3 is a plan view for explaining a modified embodiment of the showerhead of FIG.

4 is a perspective view of a major cutaway portion of the showerhead of FIG. 2;

5 is a perspective view illustrating a main portion of the showerhead according to a modified embodiment of FIG. 4;

6 is a sectional view of a showerhead according to another modified embodiment of FIG. 4;

7 is a side cross-sectional view of the showerhead of FIG. 6;

8 is a cross-sectional view of the showerhead according to another modified embodiment of FIG. 4;

9 is a side cross-sectional view of main parts of a showerhead and a cross-sectional view for explaining the operation of the showerhead according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: atomic layer deposition apparatus 110: process chamber

111: chamber exhaust 120: susceptor

121: rotation axis 125: rotation drive unit

130: shower head 131: injection hole

131a: injection line 131b: purge hole

132: injection zone 132a, 132b: source zone

132c and 132d: purge zone 133: jet intake group

135: intake hole 135a: intake line

140: exhaust line 141: exhaust hole

160: discharge portion 165: exhaust portion

W: Substrate

Claims (8)

Process chambers; A susceptor rotatably mounted in the process chamber, the susceptor having one or more substrates seated thereon; A shower head provided in an upper portion of the process chamber and having at least one source region in which source gas is injected and at least one purge region in which purge gas is injected into the substrate; And An exhaust line disposed at a boundary between the source region and the purge region in the shower head to exhaust exhaust gas in the process chamber; Including, And a plurality of injection holes for injecting the source gas and a plurality of intake holes for sucking the exhaust gas in the source region, wherein the injection holes and the intake holes are alternately disposed. The method of claim 1, The source region is, A plurality of injection lines defined by a plurality of injection holes disposed along a straight line; And A plurality of intake lines defined by a plurality of intake holes arranged along a straight line parallel to the injection line; Is formed, And the injection line and the intake line are alternately arranged to form an injection intake group. delete The method of claim 2, And the source region is provided with a plurality of spray intake groups radially formed along a radial direction of the shower head. delete delete delete The method of claim 1, And the exhaust line and the intake hole are connected to different exhaust parts.

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